Modular rim board for floor and rafter systems

ABSTRACT

An engineered perimeter rim board with machined or otherwise-formed modular recessed receptacles receives and secures I-joists and other manufactured joists at pre-designated spaces along the length of the rim board. The rim board provides pre-measured joist securement locations and structural enhancements by “locking” the joists into position. Receptacles machined/cut into the rim board may be of various shapes, such as a rectangular recess with a flat planar back wall, a profiled recess with curved top and bottom compartments, and/or an angled recess wherein two sidewalls converge to create a recess without a back wall for receiving joists at positions other than perpendicular to the rim board. The preferred 90-degree receptacle profile provides an I-joist web receiving slot for additional lateral support to help prevent joists from buckling, twisting or rolling over.

This application is a continuation of patent application Ser. No.10/376,556, filed Feb. 27, 2003, issuing on Jun. 7, 2005 as U.S. Pat.No. 6,901,715, which claims priority of provisional application Ser. No.60/360,763, filed Feb. 27, 2003, entitled “Pre-Machined Rim Board forUse with Manufactured I-Joists,” the disclosure of which is incorporatedherein by this reference.

BACKGROUND OF THE INVENTION

1. Field of Invention

This invention relates to a pre-machined, engineered, perimeter rimboard that incorporates joist recessed receptacles that may bemanufactured to be universally compatible with all existing andpreferably all future I-joists and other manufactured joist products.This invention may be one component in a series of products thatcomprise installation and structural enhancements for wood framebuilding construction projects.

2. Related Art

Numerous companies manufacture I-joists, dimensional lumber and otherwood products which are used as floor joists and roof rafters in framebuilding construction. According to I-joist manufacturers, theadvantages of I-joists over solid lumber and other wood productsinclude: a) lightweight for ease of handling, b) product uniformity andconsistency, c) availability of long lengths, d) high structuralintegrity, and e) the conservation of old growth forests through use ofcomposite wood fiber materials.

I-joists are comprised of top and bottom flanges made of solid wood,laminated veneer lumber (LVL) and/or oriented strand lumber (OSL), thetop and bottom flanges being at the top and bottom edges of a thincenter web made of plywood, oriented strand board (OSB) or otherstructurally approved materials. While these products are wellengineered for uniformly distributed top load conditions, the thin webcreates unique challenges for solid, stable and secure attachments toconventional rim boards.

Presently, conventional flat-surfaced rim boards, which have rectangularcross section end profiles and which are not machined, are available inthe same depths as I-joists. The purpose of these rim boards is toprovide stability and additional load capabilities to the ends ofI-joists. Builders have to specifically measure each joist or rafterlocation before placement and attachment to conventional rim boards.

Most manufactures of I-joists publish details for securing the rim boardto joist ends by using a single 8d box or 10d box nail into each end ofboth the top and bottom flanges of the I-joist. This does not favorablycompare with the strength of three or four 16d box nails used to securerim boards onto the ends of conventional solid framing lumber.Additionally, a minimal attachment of a conventional non-machined rimboard to I-joists may not, in many cases, meet today's strict lateralload (wind and seismic) code requirements. Many architects, engineersand designers are faced with specifying special on-site supplementalblocking inside the rim board, which is time consuming and tedious, andwhich requires additional materials and more labor and creates potentialchallenges for cutting squarely and to exact proper length.

Practically speaking, many of these on-site structural details, such asthe on-site supplemental blocking, are improperly followed or ignoredaltogether in the field. Therefore, a need exists for a pre-machined rimboard product that is easy to install and enhances the structuralstability of this important connection while saving time and expense.Further, a need exists for a product that facilitates framing accuracyfor all joist and rafter installations while protecting the integrity ofI-joists in particular. The present invention meets these needs.

BRIEF SUMMARY OF THE INVENTION

The present invention provides apparatus comprising a rim board, for usein a floor or rafter perimeter, which has at least one, and preferably aplurality of, receptacles for joist/rafter members along the length ofthe rim board. Preferably, each receptacle is in the form of a recessformed/cut into the body of the rim board in a size and shape adaptedfor receiving an end of the joist/rafter. Thus, the preferred apparatusis a pre-machined, engineered rim board system with modular recessedreceptacles at pre-designated spacing, and methods of using the same.The recesses may be generally rectangular, I-shaped to fit an I-joist,profiled to assist in insertion of the joist/rafter into the recess,and/or other shapes that optimally fit various joists/rafters. An objectof the invention is to provide an easy-to-use, cost effective, modularrim board with pre-measured recessed locking receptacles that improvesthe quality, performance and efficiency of I-joist and other floor androof framing systems. The rim boards may be provided in different sizesuniversally conforming to I-joists, dimensional lumber and othermanufactured joist products. The invented rim board design improves theoverall performance and installation of I-joist and other floor and roofframing systems.

It is an objective of the present invention to improve the quality,structural stability and speed of installation of joist systems. Otherobjectives are to enhance the nailing capabilities and to maintainperformance and integrity of I-joist products in particular. Theinvented rim board, when properly installed and secured to joist ends,provides improved lateral loading capacity to floor systems relative tonormal end-nailing without additional blocking. The dimensions andshapes of the recessed receptacles help prevent undesirable twisting,buckling or rolling of the joist. The receptacles reduce the shearingforces imparted upon nails used to secure the connection. This factorbecomes a critical enhancement for I-joist framing systems withsignificant lateral loads due to seismic or high wind conditions.

Other functional purposes of the preferred rim board are to; a) allowfor increased surface bearing area for the ends of joists on the platebelow due to the penetration of the joists into the receptacles, and b)provide for superior nailing patterns for securing joists to the platedue to improved penetration of the I-joist into the receptacle whichpermits toe nails to be moved away from the edge and toward the centerof the plate. Preferred embodiments of the rim board include areceptacle that is profiled and that has a web support slot, whichprovides vertical stability to the thin web of I-joists undercompressive loads.

A further objective of this invention is to make the installation ofjoist systems more user-friendly. The uniform pre-designated locationsof the modular recessed receptacles eliminate the need to measure andmark the placement of each joist at the job site. This saves time,expense and reduces possibilities of installation errors.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of one embodiment of the inventedrectangular receptacle rim board (R-90), showing how it relates to atypical I-joist or dimensionally rectangular joist framing system.

FIG. 2 is an exploded perspective view of one embodiment of the inventedprofiled receptacle rim board (P-90), showing how it relates to atypical I-joist framing system.

FIG. 3 is a detail perspective side view of the rectangular receptacle(R-90) of FIG. 1 for I-joists or dimensionally rectangular joists usedwith floor or roof systems that are connected at 90-degree angles to therim board.

FIG. 4 is a detail perspective side view of the profiled receptacle(P-90) of FIG. 2 for I-joists connecting at 90-degree angles to the rimboard.

FIG. 5 is a perspective top view showing one embodiment of a method ofattaching an I-joist to a profiled receptacle rim board (P-90).

FIG. 6 is a perspective side view of one method of connecting the end ofone rim board to another using a gusset between the modular recessedreceptacles, using a P-90 rim board embodiment.

FIG. 7 is a detail perspective side view of the one embodiment of the“universal” continuous V-groove of the invented angled rectangularreceptacle) rim board (R-22.5, R-30 and R-45) for dimensionallyrectangular joists or I-joists connecting at angles other than90-degrees.

FIG. 8 is a detail perspective side view of one embodiment of theinvented profiled angled receptacle rim board for I-joist connecting atangles other than 90-degrees.

FIG. 9 is a perspective side view of the one embodiment of the invented90-degree profiled receptacle rim board (P-90) and the invented angledprofiled receptacle rim board (P-22.5, P-30 and P-45), showing how theyrelate to continuing the modular spacing of joists, and showing angledsupport blocks according to one embodiment of the invention completingthe connection of the I-joists to the angled receptacle rim boards.

FIG. 10 is a detail perspective view of how an I-joist may attach to theinvented rim boards, according to one embodiment of the invention, oneither side of the transition point from a 90-degree rim board (P-90)connecting to an angled rectangular receptacle rim board (R-45).

FIG. 11 is a detail perspective view of the exterior surface of the rimboard, according to one embodiment of the invention, showing thepreferred attributes of printed modular “cut lines” and an approvedprinted nailing pattern for edge nailing of sub-floor to rim board andrim board to plate.

FIG. 12 is an exploded perspective view of one embodiment of twoinvented support blocks that may be used according to one embodiment ofthe invention in combination with an I-joist.

FIG. 13 is a detail view of an I-joist and two invented support blocksin use with an embodiment of the rim board.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the Figures, there are shown several, but not the only,embodiments of the invented RIM BOARD for use with manufactureddimensionally rectangular joists and wood I-joists, and methods ofinstalling the same. The preferred rim board, which is currently calledthe “Speed-I-Lock™” Rim Board, comprises modular recessed receptaclesthat are designed and engineered to accept the end profiles of I-joistsand other manufactured joists made from solid lumber, reconstituted woodproducts and other approved materials regardless of dimensional size,shape and/or manufacturer. The preferred receptacle designs featurepre-measured joist spacing to facilitate accuracy and accelerate onsiteinstallation time. The rim boards may be manufactured, for example, fromsolid softwood and/or hardwood lumber; laminated veneers, reconstitutedand composite wood products using various types and/or combinations ofadhesive bonding systems; formed by extruding and/or platens compressingwood particles, fibers, strands, chips or flakes; composites such asplastics, acrylics, fiberglass, nylons and/or other synthetic fibers andmaterials in various forms and/or in combinations that can be used tocreate strong and durable products that will meet stated and evolvingindustry performance standards.

The preferred rim board recessed receptacles may be identified accordingto three general design categories. For joists joining a rim boardperpendicular to the rim board the receptacle is either (a) rectangularin shape for acceptance of both dimensional rectangular joists andI-joists of the same flange width, or is (b) specifically profiled forconformance to the unique shape of a particular I-joist. The rectangularand profiled receptacles lock the perpendicular connections of joistsinto position providing stability and resistance to lateral loads. Thethird preferred design category of receptacle is for joists joining arim board at any angle other than 90-degrees, and is a V-shaped designto universally receive one leading edge of the square cut end ofdimensional rectangular joists and I-joists.

The preferred rectangular receptacle comprises a single continuous widthcompartment which accepts the top and bottom flanges of an I-joist orthe end cross-section of a dimensional rectangular joist or rafter. Themachined sidewalls of the receptacle are straight and perpendicular tothe vertical surface plane. The depth of the recessed receptacleprovides additional space for penetration for the end of the joist tobear on the plate below.

The preferred profiled receptacle, designed specifically for I-joists,comprises two recessed flange compartments connected by a singlevertical web support slot that closely conforms to the unique endprofile of an I-joist. The top and bottom recessed flange compartmentsprovide additional lateral support and allow penetration of the end ofthe I-joists into the rim board for increased surface bearing area onthe plate. The vertical web support slot enhances the stability of theweb against collapse and failure. The preferred recessed flangecompartments are curved toward the center of the rim board. The gentleradius of this curve allows the I-joist to vertically slide downward andlock into position in a rim board that has been already properlypositioned on a plate. The gentle radius of the curve helps prevent theI-joist from hanging up on the surfaces of the recess, and particularlyfrom hanging up on a ledge or other abrupt transition from the topcompartment to the web slot. The radius of the curve is preferably inthe range of about 3-4 inches.

The preferred angled receptacle design for rim boards receiving joistsat other than 90-degree angles features continued pre-measured modularjoist spacing, but is preferably used with an additional “SupportBlock,” currently called the “Speed-I-Lock™” Support Block, when usedwith I-joists to enhance structural stability and nailing.

The invented rim board is preferably available for 90, 45, 30,22.5-degree joist angle connections and in various widths and receptacleprofiles to match existing and future joist products. The 90-degreereceptacle “lock” for the rectangular receptacle rim board,quick-referenced as the “R-90 Rim Board,” conforms dimensionally to therectangular cross-section of a specific joist, rafter or the flangewidth of connecting I-joists. The 90-degree receptacle “lock” for aprofiled receptacle rim board, quick-referenced as the “P-90 Rim Board,”conforms to the unique and specific end profile of a connecting I-joist.

The angled receptacle rim board with 22.5, 30 and 45-degree modularreceptacles utilizes V-shaped compartments which lock-in one leadingedge of the square cut end of a joist. The V-shaped compartment may becontinuous and uniform across the entire width of the surface plane ofthe angled rectangular receptacle rim board, quick-referenced as the“R-22.5,” “R-30” and “R-45” rim board, for universal compatibility withall commercially-preferred joists. All angled rectangular receptaclesare shaped to universally receive square cut ends of all joists. Also,the V-shaped receptacles can be profiled with separate top and bottomV-shaped compartments on the surface plane of the angled profiledreceptacle rim board, quick-referenced as “P-22.5,” “P-30” and “P-45”rim board, that conforms to and accepts the flanges of I-joist productsonly. Eliminating special angled end cutting of joists on-site can savetime in measuring, cutting and equipment setup. The preferred methods ofconnecting an I-joist to an angled receptacle rim board require anadditional invented product, the support block, with corresponding cutangled edges to complete the connection of the I-joist to the rim board.

The invented rim boards can be used with a wide variety of diverse andcustom designed building plans. The rim board system permits the use ofconvenient and assorted depths and lengths of rim boards. The systemincludes optional pre-measured and modular printed “cut lines” betweenreceptacles to assure uniformity in modular space positioning andcontinuation with the connecting rim boards. The rim boards may be cutand adapted on the job site to fit virtually any custom layout thedesigner/architect may create. Additionally, approved nailing patternsmay be printed along the rim board edges to facilitate proper nailingconnections without penetration of nails into receptacles.

Rim board receptacles will be available for but not limited to 8″, 16″,19.2″ and 24″ on-center spacing of joists. These modular spaces willcontinue an accurate joist configuration even when a rim board anglesoff at 22.5, 30 or 45-degrees from the initial rim direction.

The preferred methods for attaching a joist to the invented rim boardcomprise steps that are easily done with little or no measurement andmarking of joist locations due to the invented “modular” system thatprovides receptacles for joists at predetermined locations. The rimboard is installed from a pre-selected starting point at one corner ofthe building and is minimally fastened to the perimeter of a plate inpreparation to accept the joists. Joists are then cut to appropriatelength, visually aligned and lowered or inserted into the recessedreceptacle of the rim board.

When the rectangular receptacle rim board is chosen, installation of thejoist in the rim board is done in a simple and efficient manner, withthe joist end being slid directly into the receptacle, from either aposition above the rim board or in front of the rim board. Wheninstalled in the recessed receptacle, the end of a joist is “locked” inthe rim board with lateral movement restrained by the side walls of therecessed receptacle. Final steps will include further securing of therim board and the joists to the plate. I-joists should be always securedto the plate and to the rim board according to the preferred nailingschedule specified by the I-joist manufacturer.

When the preferred profiled receptacle rim board is chosen, installationof the joist in the rim board may still be done in a simple andefficient manner, wherein as the I-joist bottom flange is lowered intothe 90-degree profiled receptacle rim board (P-90 Rim Board), it travelsalong its guided path down through the top flange compartment, slidesover the preferred gently-curved surfaces of the profiled receptacle,and proceeds downward over the vertical web support slot before droppingand “locking” into place with the joist top flange in the top flangecompartment and the joist bottom flange in the bottom flangecompartment. Thus, the preferred curved “slide and lock” feature of theP-90 receptacle allows for a generally trouble-free and smoothinstallation that may not be experienced if all side walls, corners andedges were machined vertical and square, as in the optional andalternative method for machining the recessed receptacle that results,for example, in a rectangular receptacle rim board.

Now referring specifically to the Figures by number:

FIGS. 1 through 13 represent views of the preferred embodiments of theinvented rim board. The rim board designs will be used preferably byframers when constructing floor and roof systems with I-joists and/orother manufactured wood joist products. The invented rim board 10, 20,30 and 40 offers structural and nailing enhancements relative to thepresent industry standard. Additionally, the products save installationtime and improve the layout accuracy in the field.

FIG. 1 shows how a typical I-joist 50 and rectangular dimensional joist60 relate to the invented rectangular receptacle rim board (R-90) 10when attaching perpendicularly to the rim board. The recessed receptacle11 maintains preferred uniform modular spacing of 8″, 16″, 19.2″ or 24″on center.

FIG. 2 demonstrates how a typical I-joist 50 relates to the inventedprofiled receptacle rim board (P-90) 20 when attaching perpendicular tothe rim board. The preferred profiled receptacle is “profiled” in thatit has an I-shape outline, which is preferred but not absolutelynecessary for the I-joist. (See FIG. 1, wherein a rectangular receptacleis used for both a rectangular joist and an I-joist). The recessedprofiled receptacle 21 maintains preferred uniform modular spacing of8″, 16″, 19.2″ or 24″ on center.

FIG. 3 demonstrates the preferred basic form and dimensions of therectangular recessed receptacle (R-90) 11 for standard 90-degreerectangular receptacle rim boards 10. The receptacles are machined toconform generally to the various widths of rectangular shaped joistand/or the flange widths of I-joists. Each receptacle is a recessedrectangular compartment with a back wall 12 and two vertical side walls13 which are perpendicular to the surface plane 14 of the rim board.Once installed into the rim board, the joists are “locked” into place byvirtue of lateral movement being restrained by the sidewalls 13.

FIG. 3 Note: A=Varies (1⅛″ to 1¼″ preferred)

-   -   B=Varies (¼″ to ⅜″ preferred)    -   C=Joist width (or flange width)+ 1/16″ (preferred)    -   D=Joist depth

FIG. 4 demonstrates the preferred basic form and dimensions of theprofiled recessed receptacle (P-90) 21 for a standard 90-degree profiledreceptacle rim board 20. The receptacles are machined to conformgenerally to the various profiles of I-joists. Each receptacle comprisestop 22 and bottom 221 recessed flange compartments near the top edge andthe bottom edge of the rim board, respectively. The top recessed flangecompartment 22 opens from the top and features a back wall thatcomprises a flat back wall 23 at the upper end of the top recessedflange compartment, and curved riser portion 24 that curves from theflat back wall surface 23 toward the surface plane 14 of the rim boardcompleting the top compartment at the transition point 25 towards thecenter of the rim board. In other words, the riser portion 24 curvestoward the viewer in FIG. 4, “forward” toward the front surface of therim board 20. The back wall surface 23 and the riser portion 24,therefore, may be said to form a generally concave top compartment wall,preferably wherein there is no lip or other obstacle at the top edge ofthe compartment to hinder movement of the joist into the top compartmentfrom above. The top recessed flange compartment 22 also has side walls26 that extend perpendicularly from the back wall 23.

The bottom recessed flange compartment 221 has similar, and preferablythe same, forms 231, 241, 251 and 261 as the top recessed flangecompartment except that they are reversed in position to open up to thebottom edge of the rim board. The flange compartments are sized andmachined to accommodate various sizes of I-joist flanges.

The top and bottom flange compartments are preferably shaped and sizedthe same so that orientation of the rim board is not crucial and in factthe rim board may be reversed edge-to-edge without the I-joisthanging-up on non-curved surfaces during the step of lowering theI-joist into the receptacle or during the less-frequent step of raisingthe I-joist up out of the receptacle. However, as less-preferredoptions, only one of the compartments or none of the compartments mayhave curved back wall surfaces. For example, a rim board may have topflange compartment with a curved lower back wall surface and a bottomflange compartment with a non-curved back wall surface. Such aless-preferred option would result in the rim board having one preferredorientation with the curved top flange compartment at the top, becausereversing such a rim board edge-to-edge would tend to allow I-joisthang-up on the ledge of the non-curved flange compartment duringinstallation of the I-joist into the rim board.

A vertical web support slot 27 extends vertically between the top 22 andbottom 221 recessed flange compartments with a single flat back wall 28and two vertical side walls 29 that extend perpendicularly from the backwall 28. The combination of the top and bottom recessed flangecompartments and the vertical web support slot create a recessedreceptacle that runs from the rim board top edge to bottom edge that issymmetrical around a center point, so that the rim board could beflipped edge-to-edge and still present the same recessed receptacleshape to the I-joist.

As depicted in the drawings, the general shape of the profiled recessedreceptacle (P-90) 21 and preferred gentle machined curves 24 and 241allow I-joists to “slide and lock” in place when being installed fromthe top down into a rim board that has already been positioned on aplate. The end of an I-joist may be lowered into its top flangecompartment 22, wherein the I-joist flange may progress down along theflat back wall 23, continuing to slide over the gentle curved extendedback wall 24 of the top compartment 22 without catching or becomingwedged against the rim board in an inappropriate position. As theI-joist continues its guided path in the profiled recessed receptacle21, relative to the rim board, the bottom flange of the I-joist slidesout from the top compartment 22 at the transition point of thecompartment 25 and over the area of the vertical web support slot 27 andenters the bottom compartment 221 in reverse order of sequence, that is,by sliding along or near the curve 241 and toward back wall surface 231.Finally, as the joist bottom flange slides into the bottom compartment,the I-joist top flange slides into the top compartment 22 and theI-joist web slides into the vertical web support slot 27.

During this installation, the rim board may flex slightly to accommodatethe I-joist's movement and the end of the I-joist becomes “locked” intothe recessed receptacle. This “locking” occurs by means of the top andbottom flanges “locking” into recessed flange compartments 22 and 221,wherein the top and bottom surfaces of the I-joist are flush with thetop and bottom surfaces of the rim board, and the I-joist flanges arelaterally supported by the side walls 26 and 261, thus preventinglateral movement of the flanges relative to the rim board. Also, theI-joist web “locks” into the vertical web support slot 27 due to the webbeing laterally supported by the side walls 29, thus preventing lateralmovement of the web relative to the side walls 29. Once the rim board isproperly positioned on the plate, the I-joist is permanently nailed intoplace in the rim board and both are secured to the plate according to anapproved nailing schedule.

FIG. 4 Note: A=Varies (1⅛″ to 1¼″ preferred)

-   -   B=Varies (¼″ to ⅜″ preferred)    -   C=I-joist flange width+ 1/16″ (preferred)    -   D=I-joist web width+ 1/16″ (preferred)    -   E=I-joist depth

FIG. 5 illustrates how a typical I-joist 50 is locked into the profiledrecessed receptacle 21 of the invented rim board. The standardconnection of an I-joist 50 to the invented profiled receptacle rimboard (P-90) 20 utilizes flange end nailing 51 as specified by theI-joist manufacturer.

FIG. 5 Note: Most I-joist manufacturers allow only one 8d or 10d boxnail into each of the top and bottom flanges of the I-joists.

FIG. 6 shows how two profiled receptacle rim boards (P-90) 20 can beconnected 54 to another using a gusset made from plywood, OSB, otherapproved materials or connectors 53 between the recessed receptacles 21and secured with approved box nails 52, staples or other devises.Structural engineers and designers may also specify metal tie straps,plates or other approved hardware or devises to meet requirements forthis connection. Connections 54 may be made along optional “cut lines”printed on the invented rim boards that are exactly midway between therecessed receptacles 21, as shown in FIG. 6.

FIG. 7 demonstrates the basic form and dimension of the angledreceptacle rim board 30 with the “universal” angled rectangularreceptacle 31. The receptacle is machined as an angled V-groovedcompartment 32 transversely across the entire surface 14 of the rimboard. This compartment 32 receives either the square cut leading edgeof a rectangular shaped joist or the square cut leading edges of the topand bottom flanges of an I-joist. With this embodiment, the ends of boththe rectangular-shaped joist and the I-joist can be square cut so thatone leading edge of the joist “locks” into the invented Rim board.

FIG. 7 Note: A=Varies (1⅛″ to 1¼″ preferred)

-   -   B=⅜″ (preferred)    -   C=Joist depth

FIG. 8 demonstrates the preferred basic form and dimensions of theangled receptacle rim board 40 with the angled profiled receptacle 41.This receptacle is for I-joists only and comprises top and bottommachined angled V-grooved flange compartments 42 for the top and bottomflanges of I-joists. The two sidewalls 142, 242 of these compartmentsmeet at the rearmost extreme 342 of the compartment. With thisembodiment, the end of the connecting I-joist can be square cut so thatthe one leading edge of the flanges “locks” into the compartments.Gentle machined curved surfaces 43 are present where the angledV-grooved flange compartments curve (forward toward the view in FIG. 8)towards the surface plane 14 of the center of the rim board.

FIG. 8 Note: A=Varies (1⅛″ to 1¼″ preferred)

-   -   B=⅜″ (preferred)    -   C=Joist depth

FIG. 9 illustrates how a typical invented 90-degree profiled receptaclerim board (P-90) 20 merges with a “universal” angled rim board (R-45) 30and the modular spacing of joists are maintained through the transitionfrom 90-degrees to a selected angled connection. When I-joists areattached to an angled rim board the use of another product, calledSpeed-I-Lock™ angled support block 70, is required to complete theconnection.

FIG. 9 Note: angled support blocks 70 are not used with dimensionallyrectangular joist products.

FIG. 10 details how the modular spacing of the I-joist 50 is maintainedduring the transition from the standard 90-degree rim board 20 to theangled rim board 30. By cutting the rim board 20 vertically in-linealong the left side of 26 of the subsequent recessed receptacle 21, thefirst I-joist into the angled rim board 30 automatically positions thefollowing I-joists for continued correct spacing. The V-shaped recessedflange compartment 32 of the angled rim board may be then aligned to thecorner of the extended I-joist to assure proper spacing of additionalI-joists into the angled rim board. The angled support block 70 withappropriate nails 52 completes the connection.

FIG. 11 illustrates the detailed attachment of a 90-degree rim board,with receptacles 8″ on center, and how it relates to the I-joists,sub-floor and plate. Included in the illustration are the preferredprinted “cut lines” 81 and the preferred and approved printed nailinglocations and patterns 82. The preferred “cut lines” 81, midway betweenthe receptacles, provide easy to use modular pre-measured cutting guidesto assure proper splicing and accurate repetitive continuation of thereceptacles and I-joist spacing. The nail placement indicator marks 82provide exact locations for recommended, approved and preferred nailingpatterns. The actual logo 83 of the manufacturer can be included in theprinting process at the same time as the “cut lines” and nail markindicators. The nailing pattern along the perimeter of the sub-floorsheathing 84 should be closely aligned with the nail placement markindicators 82 printed on the rim board to avoid nailing into thereceptacles. Also, the installer should place or align the nails forsecuring the rim board to the plate 85 as close as possible to the nailplacement indicator marks to adhere to approved nailing schedules andpatterns. The rim board is appropriately toe-nailed to the approvedplate 87 with the identical nailing pattern 82 as depicted with thesub-floor sheathing. The end nailing of rim boards at corners 86 shouldcomply with manufacturer recommendations. The sheathing or sub-floor 88should be installed to conform to approved attachment specifications bythe manufacturer and building code.

FIGS. 12 and 13 illustrate embodiments of optional support blocks 100,101 that may be used with the rim board of the invention. The preferredsupport blocks 100, 101 are prefabricated, pre-cut, shaped, milled andprofiled structural blocks that preferably may be made to be universallycompatible with all existing and preferably all future I-joistmanufactured products. The preferred design of the invented supportblock may conform to the side profile of an I-joist, providing addedsupport, reinforcement, nailing surface, bearing area, and protection ofthe integrity of the connection of the I-joist to the rim board. It maybe used at load-bearing points where additional support is required,and/or at joist ends where an increased end-surface area is needed to:a) comply with code specified nailing schedules for attaching I-joiststo plates; or b) secure rim boards and trim components to I-joists.

The preferred support block provides additional compressive point loadcapacity, increases lateral stability to an I-joist web, providesimproved nailing capabilities, and assists in maintaining the integrityof the I-joist flanges. Additionally, it is easy to use, saves time andinstallation costs in the field. This product when properly nailed orstapled in place to the joist web and not to the flange providessignificant improvements to a building system using I-joists. Anapplication option is the additional use of an approved sub-flooradhesive on the contact surfaces between the support block and theI-joist, which further compliments overall performance of theinstallation.

The support block may be made available for, but not limited to: 9½″,11⅞″, 14″, and 16″ deep “I-joists”, with 1½″, 1¾″, 2″, or 2 9/16″ widetop and bottom flanges. The support block may be produced in variedsizes and out of various material types to create different performancestandards and to meet specific industry and market needs. Support blocksmay be manufactured in various widths to accommodate different bearingwall/plate widths. Additionally, angled end cuts of 45, 30, and 22.5degrees are preferably utilized to conform the support block to variousangles of connecting rim boards.

The support block comprises a “Load-Jack” portion 105 which is squarelycut to preferably be exactly the same depth as the I-joist or not morethan 1/16 inch greater depth than the I-joist depth, wherein “depth”means the dimension from the top surface of the top flange to the bottomsurface of the bottom flange of the I-joist. The support block shouldnot be cut to less depth than the I-joist depth, as this would result inthe installed support block not possessing any load-bearing capacity.The load-jack portion bears the majority of the compressive load. Also,it can receive additional nails which may be required for a joistconnection, thereby reducing risk from improper and/or excessive nailinginto the joist flanges. A properly installed support block becomes anintegral part of an I-joist so that it can be nailed directly through tothe plate to help meet nailing requirements of securing the joist to theplate. For load-jacks comprised of solid wood or composite woodproducts, a vertical grain orientation, that is, parallel to the depthdimension of the I-joist, may be specified for increased compressiveload capacity.

Also, a support block comprises a “web and flange support” portion 110that is attached to and reinforces the thin web of an I-joist, helpingto prevent buckling, rolling, or twisting of the I-joist under peak loadconditions. This web and flange support portion is preferably about1/16″ shorter than the inside distance between the flanges to preventinappropriate forces to be placed on the flanges, and hence to protectthe integrity of I-joist glue joints between the flanges and the web.The web and flange support portion preferably has machined outside edges113 to allow room for an appropriate fit in the presence of irregularglue beading that may occur in the I-joist manufacturing process betweenthe I-joist flange and the I-joist web. The vertical dimension of theweb and flange support is less than the load-jack, thus creating flangenotches 112 along the top and bottom edges. The entire support block maybe machined or milled from a single solid block or from two or morecomponents laminated together. Methods of installing the support blocks100, 101 by using nails 115, 116 are shown in FIGS. 12 and 13. AlthoughFIG. 13 illustrates two angled support blocks in use with an angledrecessed receptacle according to one embodiment of the invention, otherembodiments may include use of support Blocks with I-joists installed in90 degree rectangular and/or profiled receptacles.

In the preferred embodiments, the rim board is provided from themanufacturer with the pre-machined or otherwise-formed recessedreceptacles extending into the body of the rim board, preferably withoutany bracket or other hardware on the rim board to hold joists. Thus, itmay be seen that the invented rim board may consist of a rim boardlength having a plurality of spaced recesses, wherein each recess ispreferably adapted to hold one joist generally perpendicularly (or,optionally, within a range of about 20-90 degrees relative to the frontsurface of the rim board). Preferably, therefore, the rim board assupplied by the manufacturer does not include any hardware or otherstructure extending out from the front surface of the rim board orextending over the top or bottom edge of the rim board.

The recesses should not extend more than a prescribed amount into therim board, so as not to detract from the overall performance of the rimboard. An example of acceptable recess depth include ¼-⅜ inch deeprecesses (at their rearmost extremes, for example, dimension B in FIG.4) in a rim board 1⅛-1¼ inches thick (dimension A in FIG. 4). Theinventors expect that recesses with depths up to about ⅓ of thethickness of the rim board may be desirable, but the recess depth may begoverned by local building codes and specifications regarding minimumrim board thickness.

The term “pre-manufactured” means that the recessed receptacles andother fabrication of the rim board are done prior to delivery to the jobsite, rather than at a construction site.

The term “modular” refers to the features of pre-determined spacing andpre-machined recessed receptacles that are fabricated before delivery tothe construction site. This allows the product to be delivered andinstalled without adapting the rim board to any significant extentexcept perhaps cutting the rim board to length, connecting rim boardsend-to-end, and nailing rim board to plate, providing optional supportblocks against I-joists, and nailing sub-floor to the rim boards. Withthe preferred system, the joist/rafter member is supported by the plateand held laterally by the sidewalls of the recessed receptacles so thatlateral movement of the joist/rafter member is restricted.

Although this invention has been described above with reference toparticular means, materials and embodiments, it is to be understood thatthe invention is not limited to these disclosed particulars, but extendsinstead to all equivalents within the scope of the following claims.

1. A rim board for a flooring or rafter system, the rim board having: afront surface, a top edge, a bottom edge, a transverse depth betweensaid top edge and bottom edge, a first end, a second end, a lengthbetween said first end and second end, and a plurality of generallyI-shaped recesses in said front surface for receiving an I-shaped end ofan I-joist.
 2. A rim board as in claim 1, wherein each of said recessesextends from the top edge to the bottom edge.
 3. A rim board as in claim1, wherein each of said recesses has a top compartment near said topedge and having a width, a bottom compartment near said bottom edge andhaving a width, and a slot connecting said top compartment and saidbottom compartment and having a width that is less than the width of thetop compartment and less than the width of the bottom compartment.
 4. Arim board as in claim 3, wherein said top compartment and said bottomcompartment of each recess are shaped and sized the same so that saidrecesses are configured for an I-joist to be reversible top-to-bottom ineach recess.
 5. A rim board as in claim 3, wherein said top compartmenthas a flat back wall.
 6. A rim board as in claim 3, wherein said topcompartment has a back wall with a curved portion.
 7. A rim board as inclaim 3, wherein said bottom compartment has a flat back wall.
 8. A rimboard as in claim 3, wherein said bottom compartment has a back wallwith a curved portion.
 9. A rim board as in claim 3, wherein said frontsurface lies substantially on a front surface plane, and said topcompartment has a back wall with a curved portion that curves outwardtoward the front surface plane near a transition between the topcompartment and said slot.
 10. A rim board as in claim 3, wherein saidfront surface lies substantially on a front surface plane, and saidbottom compartment has a back wall with a curved portion that curvesoutward toward the front surface plane near a transition between thebottom compartment and said slot.
 11. A rim board as in claim 3, whereinsaid top compartment has a back wall with a curved portion and saidbottom compartment has a back wall with a curved portion.
 12. A flooringor rafter system comprising: a rim board having a front surface, a topedge, a bottom edge, a transverse depth between said top edge and bottomedge, a first end, a second end, a length between said first end andsecond end, and a plurality of generally I-shaped recesses in said frontsurface; and a plurality of I-joists, each having a generally I-shapedend extending into one of said plurality of said generally I-shapedrecesses in the rim board.
 13. A flooring or rafter system as in claim12, wherein each of said I-shaped recesses comprises a top compartmentreceiving a top flange of the I-joist, a bottom compartment receiving abottom flange of the I-joist, and a web-support recess connecting saidtop compartment and said bottom compartment and receiving a web of theI-joist.
 14. A flooring or rafter system as in claim 12, wherein each ofsaid generally I-shaped recesses has a generally I-shaped back wall. 15.A flooring or rafter system as in claim 12, wherein the front surface ofthe rim board lies substantially on a front surface plane, and each ofsaid generally I-shaped recesses further has side walls extending intothe rim board transverse to the front surface plane.
 16. A flooring orrafter system as in claim 13, wherein said web-support recess has awidth equal to 1/16^(th) inch greater than the width of the I-joist weband the top compartment has a width equal to 1/16^(th) inch greater thanthe width of the top flange of the I-joist, and the bottom compartmenthas a width equal to 1/16^(th) inch greater than the width of the bottomflange of the I-joist.
 17. A flooring or rafter system as in claim 12,wherein the I-joist comprises a top flange, a bottom flange, and a webconnecting the top flange and the bottom flange, and the system furthercomprises a support block connected to the I-joist, the support blockhaving a support portion attached to the web of the I-joist and aload-jack portion extending from the support portion and along a sidesurface of the top flange to near said top edge and along a side surfaceof the bottom flange to near said bottom edge.
 18. A flooring or raftersystem as in claim 17, wherein the load-jack portion has a depthdimension parallel to the depth of the I-joist, said depth dimension ofthe load-jack being in the range equal to, and up to 16^(th) inchgreater than, the depth of the I-joist for bearing a compressive load.19. A flooring or rafter system as in claim 17, wherein said supportportion has a depth dimension parallel to the depth of the I-joist thatis less than a distance between said top flange and said bottom flange.20. A flooring or rafter system comprising: a rim board having a frontsurface, a top edge, a bottom edge, a transverse depth between said topedge and bottom edge, a first end, a second end, a length between saidfirst end and second end, and a plurality of generally V-shaped recessesin said front surface spaced along the length of the rim board; and aplurality of joists, each having opposing first and second sides thatare parallel to each other and parallel to the length of the joist, andan end with an end surface perpendicular to said first and secondelongated sides; wherein the end of each of said joists is received inone of said V-shaped recesses, and the joist extends from the rim boardwith its length being at an angle other than 90 degrees to the length ofthe rim board.
 21. A flooring or rafter system as in claim 20, whereinsaid V-shaped recesses each extend all along the depth of the rim boardfrom top edge to bottom edge.
 22. A flooring or rafter system as inclaim 20, wherein each of said V-shaped recesses consists of two wallsmeeting each other at a rearmost extremity of the V-shaped recess.
 23. Aflooring or rafter system comprising: a rim board having a frontsurface, a top edge, a bottom edge, a transverse depth between said topedge and bottom edge, a first end, a second end, a length between saidfirst end and second end, and a plurality of pairs of generally V-shapedrecesses in said front surface spaced along the length of the rim board,said pairs each comprising a generally V-shaped top recess near said topedge and a generally V-shaped bottom recess near the bottom edge; and aplurality of I-joists, each having a top flange, a bottom flange, and aweb, wherein the top flanges of said plurality of I-joists are receivedin the top recesses and the bottom flanges of said plurality of I-joistsare received in the bottom recesses; wherein the I-joists extend fromthe rim board at an angle other than 90 degrees.
 24. A flooring orrafter system as in claim 23, wherein each of said V-shaped top recessesconsists of two curved walls.
 25. A flooring or rafter system as inclaim 23, wherein each of said V-shaped bottom recesses consists of twocurved walls.